"Since Ultimates ended, I'd been less and less involved in a collaborative process at Marvel," he told Comic Book Resources.

"They now had their various brain-trusts, architects or whatever the gang was calling themselves, and that was what led their creative process. It seemed a very closed shop and not what it was like when I signed up to do Ultimates at all.

"I felt like they wanted an illustrator not a creator, and that was very frustrating to me. I'd submitted several proposals for various series, getting nowhere; [Ultimate Captain America] was dropped, and I didn't even feel involved in the story I was working on. It really felt like I wasn't contributing the way I wanted to be."

Hitch continued: "Obviously the work I did there over more than ten years is a true high point in my career and, in looking at the Marvel movies, clearly influential, but I guess there's a time when you feel like you don't know anybody at the party anymore or nobody's laughing at your jokes and it's time to call a cab.

"Possibly, had I known the [Age of Ultron] series was longer than the five issues I'd originally thought and if I hadn't had the Cap book pulled from under me, I may never have considered moving on, but stuff changes I guess."

He added that "there's no regret or bitterness" and that he "had an amazing time" while working for the publisher.